SnowfallPress...Create single web page (PHP, etc.. depending on your server and development preference). Have the e-junkie IPN call go that page, then call the Snowfall Press Gateway server with using the Snowfall Press standard API.
I truly thank you for the suggestion. This is exactly what we had in mind. Or, we planned to use Magento instead of e-junkie, since the shopping cart can apparently integrate with Snowfall. But this seems to be overkill because we will only be selling 1 product along with a few "free downloadable gifts". It seems that creating a single PHP page that calls to both makes sense.
The only problem is that I believe the Snowfall API also attempts to send callbacks to indicate the product was shipped, etc. So theoretically we would need another page (or at least PHP functions on the same page) to accept those calls and process them. Otherwise, we will be unable to display shipment tracking to the buyers, correct? Because as far as e-junkie.com is concerned, the transaction is complete once PayPal confirms payment and the electronic items are downloaded.
Am I correct in my thought process, E-junkieGuru / SnowfallPress?